Tiny silicon nano-wires (SiNWs) were synthesized on silicon wafers by the chemical vapor deposition (CVD) technique. The morphology and structure of tiny SiNWs were analyzed by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The results indicate that the tiny SiNWs were part-crystalline structure and were about 3nm in minimal diameter. Based on the line shift of Raman spectra, the structure transform of the tiny SiNWs was discussed. The defect-inducing growth mechanism will probably provide a new method for the minimum of the one-dimensional nano-materials.